Narrative:

First officer, was flying, I was completing the after takeoff checklist. After completion, I looked up at the altitude select which had 4000 ft in it -- at the time we were climbing through 5000 ft. I told the first officer to descend immediately -- at that time ATC called to ask our altitude -- we were then cleared to 11000 ft. During the flight home, we discussed how the altitude select portion of the autoplt had not been engaged. I remember selecting the altitude select on the autoplt prior to ramp departure, however, I did not confirm that it was illuminated on the autoplt condition panel. (It will be checked from now on.)

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Original NASA ASRS Text

Title: THE FO WAS FLYING, THE CAPT WAS COMPLETING THE AFTER TKOF CHKLIST. AFTER COMPLETION THE CAPT NOTICED THE ALT SELECT WAS ON 4000 FT AND THE ACFT WAS CLBING THROUGH 5000 FT. THE CAPT TOLD THE FO TO DSND IMMEDIATELY BACK TO 4000 FT. AT THAT TIME ATC CALLED TO ASK THE ALT AND THEN CLRED THE FLT TO 11000 FT.

Narrative: FO, WAS FLYING, I WAS COMPLETING THE AFTER TKOF CHKLIST. AFTER COMPLETION, I LOOKED UP AT THE ALT SELECT WHICH HAD 4000 FT IN IT -- AT THE TIME WE WERE CLBING THROUGH 5000 FT. I TOLD THE FO TO DSND IMMEDIATELY -- AT THAT TIME ATC CALLED TO ASK OUR ALT -- WE WERE THEN CLRED TO 11000 FT. DURING THE FLT HOME, WE DISCUSSED HOW THE ALT SELECT PORTION OF THE AUTOPLT HAD NOT BEEN ENGAGED. I REMEMBER SELECTING THE ALT SELECT ON THE AUTOPLT PRIOR TO RAMP DEP, HOWEVER, I DID NOT CONFIRM THAT IT WAS ILLUMINATED ON THE AUTOPLT CONDITION PANEL. (IT WILL BE CHKED FROM NOW ON.)

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.